RF immunity measurements can be performed by using various methods dependent on the standard and the frequency range.

Some common methods of coupling the RF energy to the device are:

Stripline and TEM Cell Methods (ISO 11452-3 & ISO 11452-5) - The harness connected to the device is extended and positioned centrally between the septum and ground plane of the Stripline. This device can generate RF fields well in excess of 200V/m with relatively low RF injected power levels.

Free Field Method (ALSE) (ISO 11452-2) - The device and its extended harness are positioned over a ground plane. A radiating antenna is positioned 1 metre away from the device. Field levels of around 200V/m can be generated using a horn antenna over the frequency range 200MHz to 3100MHz.

Bulk Current Injection Method (ISO 11452-4) - An injection probe is positioned around the devices harness and RF energy is injected into the injection probe. This method is used in the frequency range 1MHz to 400MHz with injected levels of up to 400mA (frequency dependant).

RF emission measurements can be performed using the following methods:

Conducted RF Emissions (CISPR 13 & CISPR 25) - Conducted RF Emissions produced by the device and induced into the vehicles’ DC supply system on both the positive and negative lines are measured via 5 µH Line Impedance Stabilisation Networks (LISN’s).

Radiated RF emissions (CISPR 12, CISPR 13 & CISPR 25) - Measurements of radiated RF emissions produced by the device and emitted through the air are performed over a metallic ground plane inside a fully anechoic RF shielded enclosure. The counterpoise of the Active Rod Antenna is bonded to the ground plane.

Transient Immunity (JASO D 001-94 & ISO 7637) - Conducted Transient Emissions produced when switching inductive loads on and off can be captured and assessed. Transient emissions produced by devices in a vehicle may cause interference to other devices in the vehicle. Transients phenomena detailed in ISO 7637 can be simulated and applied to signal and power supply lines of devices to ensure they will be immune to interference when installed in the vehicle.

Electrostatic Discharge (ISO 10605 & IEC 61000-4-2) - Electrostatic discharges are common events in vehicles particularly as occupants enter and exit a vehicle after it has been travelling. These events can cause permanent damage to sensitive electronic circuitry. Electrostatic discharges can be applied to the electronic devices using a variety of networks using either the Air or Contact discharge method up to a voltage of ±30kV.

EMC Measurements can also be performed in accordance with the majority of international standards including vehicle manufacturer’s own EMC standards:

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